Computer programs for estimating energy performance and/or modeling purely hypothetical cooling systems are known. Such programs can provide a computational model of a system and theoretical estimates of energy usage of such model of the system. The theoretical estimates are based on a set of data from a database. The theoretical estimates do not provide the real cost of an actual existing system based on real data, real cost of an existing system with a hypothetical modification (e.g. addition or deletion of a component), or cost of the existing system in real-time.